Effects of Hen Age and Forced Molting Programs on Egg Quality Traits in Laying Hens

The aim of this study was to determine the effects of hen age and forced molting programs on egg quality during the postmolt period. The experiment was con-ducted using 320 Hy-Line W36 hens (63 and 75 week of age) randomly assigned to experimental groups (five replicates of eight hens for each treatment). The ex-perimental design of the study was a 2 × 4 factorial arrangement of a completely randomized design. Eight treatments were compared in a 2 x 4 factorial arrange-ment with two age treatments (63 and 75 weeks of age) and four forced molting treatments [feed withdrawal (FW), 100% alfalfa (A), 50% alfalfa and 50% oats (AO), and 100% oats (O)]). The respective diet and water were allowed ad libi-tum, and hens were placed on an artificial lighting program of 8L:16D during the 10 d molt period. At 11 d, all hens were fed a layer diet and the lighting program was changed to 16L:8D. Three eggs from each replicate were analyzed for egg quality traits on every two weeks from week 3 to week 36 during the postmolt period. Hen age had no significant effect on egg quality traits in the postmolt period. Molting methods had a significant (P 0.05) effect only on egg weight during the postmolt period. The O group had significantly (P 0.05) greater egg weight than the FW group. However, there were no significant differences among molting treatments for shape index, specific gravity, shell strength, albumen height and Haugh units during the postmolt period. Our results indicate that hen age did not influence egg quality during the postmolt period. In addition, as a non-feed withdrawal method, especially the O program can be used successfully for forced molting.